5 R rifling - Is it better?

[Litehiker]

5 R rifling, with its odd number of lands and grooves has each land opposing a groove. It also has radiused groove corners, supposedly giving a better gas seal.

It has been claimed that 5 R rifling deforms a bullet jacket less than 6 or 8 groove rifling. For long range shooting this supposedly helps the bullet retain its original shape for better flight characteristics.

So, what are the real world internal and external ballistic advantages of 5 R rifling?

Eric B.

 

[elkaholic]

5 R rifling, with its odd number of lands and grooves has each land opposing a groove. It also has radiused groove corners, supposedly giving a better gas seal.

It has been claimed that 5 R rifling deforms a bullet jacket less than 6 or 8 groove rifling. For long range shooting this supposedly helps the bullet retain its original shape for better flight characteristics.

So, what are the real world internal and external ballistic advantages of 5 R rifling?

Eric B.

I build quite a few rifles and had this same question so I asked the tech at Krieger. They build both 4 and 5 groove and I personally have shot them both, and in fact, currently have a couple. When I asked him which was better, his answer was they are equal as far as accuracy, cleaning, etc. I knew he shot competition so i asked him what he shot? His answer "all of mine are 4 groove"! 5r is all the rage these days, and they are no doubt good. My answer to you is, buy which ever one you like from a good barrel maker like Krieger, Bartlein, etc. and you will be fine......Rich

 

[Broz]

I have probably talked about my ole 300 win so many times it gets redundant. But I do think it's history may apply here.

Back when I first had it built, it was assembled with a Krieger 4 grove , 28" Sendero contour, .820 muzzle. 150 rounds later almost every single load shot 1 1/2" at 100 yards. I called Krieger , I was talked down to for questioning the Krieger 4 grove on a 30 cal. They simply said it was not the barrel and I was on my own. I called Tim North at Broughton and bought another barrel. This time 5C (which I understand to be close to the same as 5R) same length, same twist, same contour. I took the rifle back to the same smith. He re-barreled it. Same reamer, same crown, same brake. And yes I had shot the first barrel with brake removed to be sure there was no issues. I took it home and almost every group I tried was under 1/2" at 100. The finished load shoots .2 to .3 moa for 3 shot groups repetitively. Still does 1500+ rounds later.

What does this mean? I think it means I had a bad barrel. Do I think it was because it was a 4 grove? No, probably not. Will I buy more Krieger barrels, yes, I have since. I will I buy another 4 grove. NO. Will I buy more 5C and 5R's? Yes Sir, I have bought many and all shoot awesome to way out there.

I should also note, some of the most consistent barrels that have shot consistently under .5 moa have been 6 grove Harts. So, I guess I favor the 5's and 6's and if they are 5R or 5C all the better.

Jeff

 

[MudRunner2005]

I prefer 5R...The shape and design is better in every way, in my opinion, and from my experiences.

Other wrong with an equal-groove barrel, as long as it's been hand-lapped, but I do honestly prefer the 5R rifling.

 

[elkaholic]

I have probably talked about my ole 300 win so many times it gets redundant. But I do think it's history may apply here.

Back when I first had it built, it was assembled with a Krieger 4 grove , 28" Sendero contour, .820 muzzle. 150 rounds later almost every single load shot 1 1/2" at 100 yards. I called Krieger , I was talked down to for questioning the Krieger 4 grove on a 30 cal. They simply said it was not the barrel and I was on my own. I called Tim North at Broughton and bought another barrel. This time 5C (which I understand to be close to the same as 5R) same length, same twist, same contour. I took the rifle back to the same smith. He re-barreled it. Same reamer, same crown, same brake. And yes I had shot the first barrel with brake removed to be sure there was no issues. I took it home and almost every group I tried was under 1/2" at 100. The finished load shoots .2 to .3 moa for 3 shot groups repetitively. Still does 1500+ rounds later.

What does this mean? I think it means I had a bad barrel. Do I think it was because it was a 4 grove? No, probably not. Will I buy more Krieger barrels, yes, I have since. I will I buy another 4 grove. NO. Will I buy more 5C and 5R's? Yes Sir, I have bought many and all shoot awesome to way out there.

I should also note, some of the most consistent barrels that have shot consistently under .5 moa have been 6 grove Harts. So, I guess I favor the 5's and 6's and if they are 5R or 5C all the better.

Jeff

Hi Jeff! I think you did get a bad barrel; probably one in a thousand you lucky dog!! I have the EXACT same barrel on my 30/375 S.I. and it shoots bugholes. I shot a 3 shot group at 880 yards that measured 1.18" with it. Having said that, I have a 5r Bartlein on my 6.5 SS that shoots .0's. when I can hold it. Lots of good options.......Rich

 

[dok7mm]

Better????? I don't know, but I have 4 that are very accurate and don't copper up. I also have several four-groove Kriegers and they are equally good. I "think" that I prefer the Bartlein 5r, at least that's is what I put on last build, a 6.5 Sherman.

 

[shortgrass]

The short answer; "A good barrel is a good barrel,,,,,,, and any one of the fine barrel makers can, occasionally, make a not so good one!

 

[FEENIX]

The short answer; "A good barrel is a good barrel,,,,,,, and any one of the fine barrel makers can, occasionally, make a not so good one!

Agreed!

 

[Edd]

Actually, the short answer is "no, 5r is not better".

Even the guys at Bartlein will tell you that conventional rifling is more accurate.

 

[C.O. Shooter]

Actually, the short answer is "no, 5r is not better".

Even the guys at Bartlein will tell you that conventional rifling is more accurate.

I'm not trying to argue:

This was discussed across the street in an unrelated thread.

I read a post by "Frank" of Bartlien Barrels. He indicated no real advantage between 5/6 groove.

Found it: http://www.scout.com/military/snipe...mithing/14324617-twist-rate-and-groove-number

The number of grooves for the most part doesn't mean #$%# when it comes to accuracy and or barrel life. Anybody telling you differently is either selling something or doesn't know what they are talking about.

The only exception I will make is in regards to 6mm bullets. If your building a 6ppc benchrest type rifle and your only going be shooting 70gr. and lighter bullets.....those light weight bullets don't like the 5R style rifling. Why? Because of the short bearing surface on the jackets. The rifling/lands do the driving on the bullet and I feel the 5R doesn't bite those short jacket bullets good enough. Those short jacket bullets and the 5R rifling will shoot upper .2xx's to a flat .3xx but nothing better that that and on a short range bench gun that won't win you any matches. So for those bullets I tell guys go with conventional rifling. This is where the lands meet the grooves at basically a 90 degree corner. I don't care if it's a 4 groove, conventional 5 groove, 6 groove, 8 groove etc...I've got a conventional 5 groove on my 6ppc gun. It will agg in the mid .1xx's at a 100 yards. Has shot groups in the .0xx's as well.

Now staying with 6mm and going to and if your shooting long heavy bullets like the 105gr. etc...then I go with the 5R. The odd number of grooves/lands don't directly oppose one another and in conjunction with the angles on the sides of the lands I feel the rifling will not distort/upset the bullet jacket as much and there fore helps fight bullet failure. Bullet failure is more of a problem for a long range shooter than a short range shooter.

I've shot barrels in everything from 2 groove up to 8 groove in calibers from .22rf up to .338 and I don't see a difference in accuracy other than the example I listed above with the 6mm's.

We've made accuracy test barrels for ammo makers, bullet makers and the gov't arsenals in .308win. with 4 groove and 5R. Also for .300wm in 4 groove, 6 groove and 5R rifling and .338 Lapua in 6 groove and 5R and all testing has shown no difference in real world accuracy.

Hope this helps!

Later, Frank
Bartlein Barrels

 

[TOM H]

I decide to rebarrel one of my 30-06 and gunsmith ordered a Bartlein 30cal 5r barrel 1/11.25 twist
@ 26" and it replace a Kreiger 1/10 twist @ 24 also chamber for the 30-06.

This is from Bartlein site

https://bartleinbarrels.com/barrel-faq/ you'll read this

Which is better 5R style rifling or conventional rifling?
In terms of accuracy and barrel life we don't see a difference. There are a lot of varying opinions on this. Some say if you want hard core accuracy to go with conventional rifling. We feel in the real world there is no real difference. The more uniform your bore and groove sizes over the entire length of the barrel, the more uniform the twist and the straighter the blank the more forgiving the barrel is going to be.

The guys at Bartlein use to work for Kreiger

 

[elkaholic]

I decide to rebarrel one of my 30-06 and gunsmith ordered a Bartlein 30cal 5r barrel 1/11.25 twist
@ 26" and it replace a Kreiger 1/10 twist @ 24 also chamber for the 30-06.

This is from Bartlein site

https://bartleinbarrels.com/barrel-faq/ you'll read this

Which is better 5R style rifling or conventional rifling?
In terms of accuracy and barrel life we don't see a difference. There are a lot of varying opinions on this. Some say if you want hard core accuracy to go with conventional rifling. We feel in the real world there is no real difference. The more uniform your bore and groove sizes over the entire length of the barrel, the more uniform the twist and the straighter the blank the more forgiving the barrel is going to be.

The guys at Bartlein use to work for Kreiger

The biggest thing I have noticed in barrel difference is when they are 3 groove. It can be a benefit for longer life and just as accurate. The down side, the wide lands are hard on bullets and in some cases , detrimental to accuracy or even tearing jackets apart at velocity.....rich i

 

[Greyfox]

I have gone through barrels in both 5R and conventional barrels in 308W for various competitions, many which involve long strings, in summer weather where the barrel gets very hot. My impression is that, while basic accuracy and barrel life(.25-.5MOA loss at 2000-2500 rds.) is comparable, the 5R seems to hold its accuracy and zero longer before there is a loss from fouling. I have shot as many as 250 rounds with no change. Also, The 5R cleans very fast, and first shot accuracy is usually unchanged. For this reason, I'm partial to the 5R for this work. I have suspected that this may a reason that the military used the 5R in the M24. My rifles(6.5x284 and 300WM) used for LRH have both 5R and conventional barrels. For this purpose I have seen no difference in accuracy, but the 5R does seem to clean faster.

 

[FEENIX]

The biggest thing I have noticed in barrel difference is when they are 3 groove. It can be a benefit for longer life and just as accurate. The down side, the wide lands are hard on bullets and in some cases , detrimental to accuracy or even tearing jackets apart at velocity.....rich i

I'm on my second Lilja 3G and very impressed with it thus far.